Sub panel install - redundant breaker?

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Old 11-22-20, 02:20 PM
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Sub panel install - redundant breaker?

If both my panels have a 100A main breaker, do I really need another 100A breaker in the main panel to feed the subpanel or can I connect directly to the panel somehow?

The main panel does not have any other breakers in it, all of them are in the sub panel....

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11-22-20, 02:51 PM
pattenp
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Not unless the panel has feed through lugs.
 
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Old 11-22-20, 02:51 PM
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Not unless the panel has feed through lugs.
 
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Old 11-22-20, 03:49 PM
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The only way to connect the wires to the main panel is with feed-through lugs as Pattenp mentioned, or from a breaker. You may not put two wires under a single lug.

If the sub-panel is in the same building it does not require a main breaker, you may use an MLO (Main Lug Only) panel.
 
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Old 11-23-20, 03:09 PM
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So there does seem to be some feed-through lugs on this old panel. It looks like the garage subpanel is already attached to them. Can I also put another subpanel on to the same lugs together with the garage panel feed?
I have attached a picture of both lugs - one above the breakers and one below the breakers....


 
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Old 11-23-20, 04:47 PM
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Can I also put another subpanel on to the same lugs together with the garage panel feed?
No, and those garage wires should not be there either. First off I highly doubt that those lugs are designed for more than one wire. Second, those wires are much smaller than the wires feeding the panel and are likely overfused, if fused at all. This needs to be corrected right away!

If you post a picture of the entire panel we can make suggestions to properly wire your panel.
 
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Old 11-23-20, 04:59 PM
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Hmmm... well it has been like that since the 60's I am guessing. The feed wire from the breaker is much heavier gauge than what goes to the garage (my pics aren't that good....
 
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Old 11-24-20, 12:50 PM
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Your main panel.....is that a Federal Pacific or Federal Pioneer panel? I believe it is so my suggestion is to replace it with a larger panel that does have feed-thru lugs. I think I would replace it with a Square D QO panel.
 
 

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